A hand-held spray gun for paint operates under the power of pressurized air. The spray gun has a nozzle and a trigger. When the user depresses the trigger, valves inside the spray gun enable the pressurized air to spray a stream of paint outward from the nozzle. If the spray gun is in a pressure mode of operation, the pressurized air is directed into the container to force the paint outward from the container to the nozzle. If the spray gun is in a siphon mode of operation, the container is vented to the atmosphere, and the paint is drawn outward from the container by the suction of the air flowing past the nozzle.